Thank you very much for the replies on Saturday.
Still haven't figured out what the problem is, but thanks to you advices, I could check that my fuel pump works, and it does.
By working backward, I could also get closer to the cause of the problem. But still don't know what to do about it.
Quote:
Originally Posted by Enoch
Hope that makes sense, am doing this while cooking dinner  |
Yes it does, and I hope you dinner was good
I've made a sketch to illustrate the problem:
FuelPumpProblemSchematic par
Voucht71, sur Flickr
The fuel pump (1) feed wire comes, through its fuse (2), from the engine management relay (3). While testing the connection, I discover that the tension at the engine management relay main feed was only +10v, where is should be +12v. To check if it is the reason it does not switch on the fuel pump, I connected the port directly to a +12v feed. And the fuel pump started to run !
So it is because I actually have only 10v coming to the engine management relay that the relay does not switch on (I have tried with spare relays, and it is the same), and so does not power the fuel pump.
Then I tracked the main feed up to the source. Everywhere I take the tension with my voltmeter, I have only 10v. But, at the level of the connector “5”, it is very weird, because I got 12v when this connector is unconnected, but as soon as I connect it, I just have 10v. So there something somewhere that is “taking” 2 volts, but I don't know what. I uncovered the wires coming from this wire of the connector, and 3 elements are connected to this 12v feed:
- the engine management relay (where my problem is)
- the port #1 of the ECU
- a relay that I can't identify, but is working, as well as the connected fuse (all yellow, originally attached to the ECU frame, not with the other relays and fuses in the fusebox)
Nothing in between, no bad contact, nothing. Just this.
Does anyone has any idea of what the problem is?
I'm very tempted to connect a 12v cable from another 12v feed to the engine management relay (3), because when I do it, everything works : the fuel pump runs, the engine start up instantly, and I let it run a couple of minutes, push the throttle pedal, and everything works perfectly.
Would there be a major problem if I did that?
Thanks.